Groundwater levels and spring flows increased in June

A map illustrates rainfall conditions in June across the St. Johns River Water Management District

A map illustrates rainfall conditions in June across the St. Johns River Water Management District

Geographic distribution of rainfall flip-flopped from May

PALATKA, Fla., July 14, 2020 — Groundwater levels across the St. Johns River Water Management District rebounded slightly in June after a late spring downward trend, while rainfall varied with above-average rainfall in the north and western portions and below-average totals in coastal and southern regions. A full report outlining hydrological conditions was presented at the district’s July Governing Board meeting.

A map illustrates rainfall conditions in June across the St. Johns River Water Management District

A map illustrates rainfall conditions in June across the St. Johns River Water Management District

Highlights included:

Rainfall

  • June rainfall varied geographically, with a flip flop from May’s rainfall trend.
  • The district’s western and northern counties received above-average rainfall last month, while in May those areas were drier. Coastal and southern counties received below-average rainfall in June, while those areas were the wet areas of the district during the previous month.
  • Counties with the highest June rainfall were Nassau, with 10.6 inches, Baker and Duval, which received 9.5 inches.
  • Flagler County had the least rainfall, with 5.7 inches.
  • Districtwide, the cumulative rainfall total over the last 12 months is 48.3 inches, which is 2.7 inches below the long-term average.
  • Counties with the greatest rainfall deficit through June were Putnam, Flagler and St. Johns counties, which continue to have a 12-month rainfall deficit of more than 10 inches. These counties have maintained this deficit since March.

Groundwater

  • Upper Floridan aquifer conditions (groundwater levels) at the end of June were mostly in the normal range throughout most of the district, increasing consistently across the district in June and reversing the downward trend of the previous month.
  • Groundwater levels are at the 56th percentile districtwide (up from the 39th percentile in May). This means that since 1980, about 44 percent of the time aquifer levels have been higher than they are now.

Surface water flows

  • Surface water flow conditions in the St. Johns River’s headwaters rose to the average or high ranges for this time of year.
  • Flow conditions in central Florida were in the average range, with the DeLand station reporting 1.2 billion gallons per day (bgd) on July 1 and 2.5 bgd at the Satsuma station.
  • Flow in the headwaters at the Melbourne station was 218 million gallons per day (mgd) on July 1, which is in the 58th percentile of flow conditions for this time of year.
  • Flow in the Wekiva River near Sanford is in the low range at 128 mgd, which is in the 10th.
  • Flow in the Ocklawaha River increased and ended June in the average range at 585 mgd.
  • Flow in the St. Marys River, at the northern border of the district, peaked at high levels in the middle of June but ended the month in the average range, at 206 mgd.

Lake levels

  • Lake Brooklyn water levels decreased 0.4 foot in June.
  • Lake Weir increased 0.2 foot during June.
  • Lake Apopka’s water level increased 0.1 foot and is level with its regulation schedule for June.
  • Blue Cypress Lake levels increased 0.6 foot and is level with its regulation schedule for June. Keeping water levels low in the Upper St. Johns River Basin helps the district prepare for greater rainfall during the tropical season.

Spring flows

  • The mean monthly flow at Silver Springs increased to 642 cubic feet per second (cfs), or 415 mgd. This is an increase of 31 cfs from May.

To learn more about rainfall totals and other hydrologic data collected, visit sjrwmd.com.

The district’s summertime water conservation message reminds water users to “Watch the Weather. Wait to Water.” Visit the district’s Water Less campaign webpage at WaterLessFlorida.com and follow the district on social media to learn ways to conserve water outdoors. #WaterLessFlorida #waterconservation #sjrwmd